Finally got round to starting to sort out the aerial and distribution 
system in our new place. To recap: there were two aerials - one high 
gain group A on crystal palace, and a contract group B on sudbury. These 
were combined (goruped combiner it turns out) onto a single downlead and 
fed into a labgear 6 way amp / splitter thence sockets around the house.

I decided to abandon the CP aerial altogether (since the digital muxes 
were almost down in the noise) and concentrate on Sudbury. Looking at 
the post switchover allocations suggested a group E aerial. However not 
being able to find a decent one of those, I took Bill Wright's advice 
and modified a group B to extend the top end.

Anyway that is now fitted and working nicely (took the opportunity to 
replace the mortar flaunching on the chimney pots at the same time as 
these were wobbling!).

I fitted a variable gain masthead amp:

http://cpc.farnell.com/jsp/level5/module.jsp?moduleId=cpc/461209.xml

Looking at the feed to the distribution amp (with the gain on the 
masthead set to minimum) we now get:

Channel Signal  Mux
          (dBuV)
39      52      D4
48      51      D3
49      52      D1
50      50      D6
54      48      D5
56      48      D2

Which seems like a reasonable starting point, with the Terry meter 
reporting a "pass" for signal to noise on all the muxes. A problem 
however is the in band the analogue signals:

44      73      BBC2
51      74      BBC1
(similar level for the others)

Which are at least 20 dB stronger than the digital muxes. (if you ramp 
up the gain on the masthead I can push these to over 99 dBuV - which is 
where my meter gives up!)

Trying this through the existing splitter amp still did not give 
adequate performance. I have come to the conclusion that the labgear is 
crap anyway (poor noise etc) and the house co-ax wiring leaves much to 
be desired. Tweaking the gain up on the masthead did not really help 
much either since I expect it was overloading the input on the splitter 
amp with the high analogue signals.

Ditching the current splitter amp altogether, and running the masthead 
on full gain, into a passive splitter got reasonable performance on one 
socket but marginal on others. Adding a lowish gain setback amp before 
the passive splitter got good performance on at least two sockets and 
reasonable on others.

So to get robust and reliable digital on all sockets I could do with a 
little more headroom coming out of the splitter.

Rewiring the house with decent CT100 will happen at some time - but not 
in a hurry (the loss one some runs is quite startling - not helped by 
the previous installer deciding to daisy chain two sockets on some of 
the runs).


Questions
=========

So should I:

Go with a better distribution amp with moderate gain on each output? If 
so any recommendations for one that is not going to be upset by the 
disparity in input levels?

Or

Try to level (or for that mater just notch filter) the analogue signals? 
(I don't care if we lose all analogue reception)

If the latter, what would be an appropriate device, and when can I order 
one from?

How easy are these to setup?

-- 
Cheers,

John.

/=================================================================\
|          Internode Ltd -  http://www.internode.co.uk            |
|-----------------------------------------------------------------|
|        John Rumm - john(at)internode(dot)co(dot)uk              |
\=================================================================/

>Questions
>=========
>
>So should I:
>
>Go with a better distribution amp with moderate gain on each output? If 
>so any recommendations for one that is not going to be upset by the 
>disparity in input levels?
>
>Or
>
>Try to level (or for that mater just notch filter) the analogue signals? 
>(I don't care if we lose all analogue reception)
>
>If the latter, what would be an appropriate device, and when can I order 
>one from?
>
>How easy are these to setup?
>


Go Freesat;?.....
-- 
Tony Sayer

tony sayer wrote:

> Go Freesat;?.....

There's no need to use language like that. He's only asking for advice.

"tony sayer"  wrote in message 
news:DgJzWpA42eZIFwwj@bancom.co.uk...
> >Questions
>>=========
>>
>>So should I:
>>
>>Go with a better distribution amp with moderate gain on each output? If
>>so any recommendations for one that is not going to be upset by the
>>disparity in input levels?
>>
>>Or
>>
>>Try to level (or for that mater just notch filter) the analogue signals?
>>(I don't care if we lose all analogue reception)
>>
>>If the latter, what would be an appropriate device, and when can I order
>>one from?
>>
>>How easy are these to setup?
>>
>
>
> Go Freesat;?.....
> -- 
> Tony Sayer

For this many outlets?
It's a good answer for some applications, but where you wish to watch and 
record different programmes at multiple outlets it's far from ideal.

I run 6 TV's and at 3 of these we also record. That would require 9 Freesat 
boxes, and mean I couldn't easily distribute FM and DAB to each outlet. I 
also distribute the output of the Sky box and the DVD/VCR meaning we can 
watch Sky pay channels and in-house channels anywhere too.

In article <g44sjj$prg$1@registered.motzarella.org>, Silk
 scribeth thus
>tony sayer wrote:
>
>> Go Freesat;?.....
>
>There's no need to use language like that. He's only asking for advice.

Its very good advice;)..

Why go to all that complication where theres a perfickly simple
alternative available?..
-- 
Tony Sayer

In article <VtidnRTPOcAAl_vVnZ2dnUVZ8radnZ2d@posted.plusnet>, Doctor D
 scribeth thus
>
>"tony sayer"  wrote in message 
>news:DgJzWpA42eZIFwwj@bancom.co.uk...
>> >Questions
>>>=========
>>>
>>>So should I:
>>>
>>>Go with a better distribution amp with moderate gain on each output? If
>>>so any recommendations for one that is not going to be upset by the
>>>disparity in input levels?
>>>
>>>Or
>>>
>>>Try to level (or for that mater just notch filter) the analogue signals?
>>>(I don't care if we lose all analogue reception)
>>>
>>>If the latter, what would be an appropriate device, and when can I order
>>>one from?
>>>
>>>How easy are these to setup?
>>>
>>
>>
>> Go Freesat;?.....
>> -- 
>> Tony Sayer
>
>For this many outlets?
>It's a good answer for some applications, but where you wish to watch and 
>record different programmes at multiple outlets it's far from ideal.
>
>I run 6 TV's and at 3 of these we also record. 

Blimey! your addicted to the telly?..

I should see someone about that!..

U need therapy M8;)..


-- 
Tony Sayer

John Rumm wrote:
> 
> Finally got round to starting to sort out the aerial and distribution 
> system in our new place. To recap: there were two aerials - one high 
> gain group A on crystal palace, and a contract group B on sudbury. These 
> were combined (goruped combiner it turns out) onto a single downlead and 
> fed into a labgear 6 way amp / splitter thence sockets around the house.
> 
> I decided to abandon the CP aerial altogether (since the digital muxes 
> were almost down in the noise) and concentrate on Sudbury. Looking at 
> the post switchover allocations suggested a group E aerial. However not 
> being able to find a decent one of those, I took Bill Wright's advice 
> and modified a group B to extend the top end.
> 
> Anyway that is now fitted and working nicely (took the opportunity to 
> replace the mortar flaunching on the chimney pots at the same time as 
> these were wobbling!).
> 
> I fitted a variable gain masthead amp:
> 
> http://cpc.farnell.com/jsp/level5/module.jsp?moduleId=cpc/461209.xml
> 
> Looking at the feed to the distribution amp (with the gain on the 
> masthead set to minimum) we now get:
> 
> Channel Signal  Mux
>          (dBuV)
> 39      52      D4
> 48      51      D3
> 49      52      D1
> 50      50      D6
> 54      48      D5
> 56      48      D2
> 
> Which seems like a reasonable starting point, with the Terry meter 
> reporting a "pass" for signal to noise on all the muxes. A problem 
> however is the in band the analogue signals:
> 
> 44      73      BBC2
> 51      74      BBC1
> (similar level for the others)
> 
> Which are at least 20 dB stronger than the digital muxes. (if you ramp 
> up the gain on the masthead I can push these to over 99 dBuV - which is 
> where my meter gives up!)
> 
> Trying this through the existing splitter amp still did not give 
> adequate performance. I have come to the conclusion that the labgear is 
> crap anyway (poor noise etc) and the house co-ax wiring leaves much to 
> be desired. Tweaking the gain up on the masthead did not really help 
> much either since I expect it was overloading the input on the splitter 
> amp with the high analogue signals.
> 
> Ditching the current splitter amp altogether, and running the masthead 
> on full gain, into a passive splitter got reasonable performance on one 
> socket but marginal on others. Adding a lowish gain setback amp before 
> the passive splitter got good performance on at least two sockets and 
> reasonable on others.
> 
> So to get robust and reliable digital on all sockets I could do with a 
> little more headroom coming out of the splitter.
> 
> Rewiring the house with decent CT100 will happen at some time - but not 
> in a hurry (the loss one some runs is quite startling - not helped by 
> the previous installer deciding to daisy chain two sockets on some of 
> the runs).
> 
> 
> Questions
> =========
> 
> So should I:
> 
> Go with a better distribution amp with moderate gain on each output? If 
> so any recommendations for one that is not going to be upset by the 
> disparity in input levels?
> 
> Or
> 
> Try to level (or for that mater just notch filter) the analogue signals? 
> (I don't care if we lose all analogue reception)
> 
> If the latter, what would be an appropriate device, and when can I order 
> one from?
> 
> How easy are these to setup?
> 
Running a variable gain amplifier at lowest gain will only increase the 
noise level. A fixed low gain amplifier would be better suited. Having 
the actual input levels to the masthead amplifier from the aerial would 
make it easier to advise you.

Glenn...

tony sayer wrote:
> In article <g44sjj$prg$1@registered.motzarella.org>, Silk
>  scribeth thus
>> tony sayer wrote:
>>
>>> Go Freesat;?.....
>> There's no need to use language like that. He's only asking for advice.
> 
> Its very good advice;)..
> 
> Why go to all that complication where theres a perfickly simple
> alternative available?..

Two answers to that:

one, I already have it - using an old cast off sky box and the disk the 
previous occupants left behind,

and two

I have a significant investment in freeview kit, including a topfield 
PVR and network connection for it.

What I don't have is a bunch of sat boxes, a multiswitch, a quad output 
LNB or any of the wiring infrastructure to make freesat a cost effective 
  multiroom setup.


-- 
Cheers,

John.

/=================================================================\
|          Internode Ltd -  http://www.internode.co.uk            |
|-----------------------------------------------------------------|
|        John Rumm - john(at)internode(dot)co(dot)uk              |
\=================================================================/

Glenn Millar wrote:

> Running a variable gain amplifier at lowest gain will only increase the 
> noise level. A fixed low gain amplifier would be better suited. Having 

The spec on that amp show a max noise of 2.6dB and a minimum gain of 
supposedly 7dB, so that ought to have had some positive benefit. However 
the min gain setting was really used just to overcome the initial 
download loss and see if the dist amp could do its stuff from there.

> the actual input levels to the masthead amplifier from the aerial would 
> make it easier to advise you.

Just as well I have not taken the ladders down yet (although you just 
incurred the wrath of SWMBO for interrupting the tennis!)

Channel @Aerial  +mast amp  +mast amp
                  min gain   max gain
39      53       56         73
48      53       57         72
49      54       59         74
50      53       56         71
54      51       55         68
56      51       55         68

Analogue bbc1 & 2 :

44      72       77         94
51      75       82       >=99

(I note the gain is a bit lower than spec at both ends - but that could 
be down to the fact I was powering the amp from my test meter and the 
batteries were getting low)



-- 
Cheers,

John.

/=================================================================\
|          Internode Ltd -  http://www.internode.co.uk            |
|-----------------------------------------------------------------|
|        John Rumm - john(at)internode(dot)co(dot)uk              |
\=================================================================/

John Rumm wrote:
> Glenn Millar wrote:
> 
>> Running a variable gain amplifier at lowest gain will only increase 
>> the noise level. A fixed low gain amplifier would be better suited. 
>> Having 
> 
> The spec on that amp show a max noise of 2.6dB and a minimum gain of 
> supposedly 7dB, so that ought to have had some positive benefit. However 
> the min gain setting was really used just to overcome the initial 
> download loss and see if the dist amp could do its stuff from there.
> 
>> the actual input levels to the masthead amplifier from the aerial 
>> would make it easier to advise you.
> 
> Just as well I have not taken the ladders down yet (although you just 
> incurred the wrath of SWMBO for interrupting the tennis!)
> 
> Channel @Aerial  +mast amp  +mast amp
>                  min gain   max gain
> 39      53       56         73
> 48      53       57         72
> 49      54       59         74
> 50      53       56         71
> 54      51       55         68
> 56      51       55         68
> 
> Analogue bbc1 & 2 :
> 
> 44      72       77         94
> 51      75       82       >=99
> 
> (I note the gain is a bit lower than spec at both ends - but that could 
> be down to the fact I was powering the amp from my test meter and the 
> batteries were getting low)
> 
> 
> 
I personally wouldn't be fitting a masthead amplifier. A good quality 
distribution amplifier with moderate gain at most, Proception 8way 5dB 
gain for example.  You don't want signals on analogue at the TV to be 
higher than 80 or digital above 60.

Your problem seems to be too much signal instead of too little.

"John Rumm"  wrote in message 
news:5rSdnfR-0-DyIvjVnZ2dneKdnZynnZ2d@plusnet...
> Questions
> =========

You need to tell us the levels straight off the aerial. However . . .

> So should I:
>
> Go with a better distribution amp with moderate gain on each output? If so 
> any recommendations for one that is not going to be upset by the disparity 
> in input levels?

Firstly do everything you can to improve the signal/noise ratio from the 
aerial. This usually means obtaining a stronger signal.
Assuming the levels thus obtained are within about +/-5dB of -2dBmV 
(analogue) and : -22dBmV (digital) use a fixed gain masthead amp. You can 
either use a low gain masthead plus a low gain multi-output amp, or a medium 
gain masthead and a passive splitter with a loss of 10dB. These ideas assume 
reasonable cable losses. If the cable losses are rather high you might get 
away with using a bit more gain, but really you should change the cables. If 
the cable losses are very high then you must change the cables. Damp/old 
cables can put a slope across muxes or notches within them, which receivers 
don't like.

Check for out-of-band signals swamping the amps. Good amps have input 
filters though.

>
> Or
>
> Try to level (or for that mater just notch filter) the analogue signals? 
> (I don't care if we lose all analogue reception)
Can't be done with passive filters, since you have adjacent muxes. Putting a 
slope on the muxes would be highly undesirable. If the analogues are 25dB 
above the digis there shouldn't be a problem. To put this in perspective, 
most amps are designed with analogue signal levels in mind. Headroom 
shouldn't be a problem. The 20dB disparity isn't a problem really because of 
digi's good c/n ratio performance.

>
> If the latter, what would be an appropriate device, and when can I order 
> one from?
A full set of active filters will cost about £450 (without looking it up).

>
> How easy are these to setup?
Very.


Bill

<uk.tech.digital-tv>
<Bill Wright>
<Sat, 28 Jun 2008 16:25:58 퍝>


> > If the latter, what would be an appropriate device, and when can I order 
> > one from?
> A full set of active filters will cost about £450 (without looking it up).
> 
> >
> > How easy are these to setup?
> Very.
> 

Would it be possible for you to put a blank line inbetween the quote and 
your reply .

Not everybody uses a news client that has different coloured text .

Or dont you care if your posts are readable by others or not ? .


-- 
www.krustov.co.uk

In article <zumdnfkVaJee2_vVnZ2dnUVZ8vednZ2d@posted.plusnet>, John Rumm
 scribeth thus
>tony sayer wrote:
>> In article <g44sjj$prg$1@registered.motzarella.org>, Silk
>>  scribeth thus
>>> tony sayer wrote:
>>>
>>>> Go Freesat;?.....
>>> There's no need to use language like that. He's only asking for advice.
>> 
>> Its very good advice;)..
>> 
>> Why go to all that complication where theres a perfickly simple
>> alternative available?..
>
>Two answers to that:
>
>one, I already have it - using an old cast off sky box and the disk the 
>previous occupants left behind,
>
>and two
>
>I have a significant investment in freeview kit, including a topfield 
>PVR and network connection for it.
>
>What I don't have is a bunch of sat boxes, a multiswitch, a quad output 
>LNB or any of the wiring infrastructure to make freesat a cost effective 
> multiroom setup.
>

Didn't you say you can't get freeview anyway earlier?..

Simple just run a signal cable from a multi output LNB?..
>

-- 
Tony Sayer

tony sayer wrote:

>> I have a significant investment in freeview kit, including a topfield 
>> PVR and network connection for it.
>>
>> What I don't have is a bunch of sat boxes, a multiswitch, a quad output 
>> LNB or any of the wiring infrastructure to make freesat a cost effective 
>> multiroom setup.
>>
> 
> Didn't you say you can't get freeview anyway earlier?..

You may recall:

http://groups.google.com/group/uk.tech.digital-tv/browse_frm/thread/af31376eece93d26/5c59b06724640147?hl=en&lnk=st&q=group%3Auk.tech.digital-tv+rumm#5c59b06724640147

Which was the state of play when we moved in - passable analogue from 
one Tx and poor from another, and only one mux limping through part time 
from the better Tx.

I did a lash-up with the original aerial and lots of amplification in 
all the wrong places to see if with enough signal level I could get 
anything useful, and did achieve at least most muxes on one TV.

So now with a new more appropriate aerial I am close to having a fully 
working multi output setup. Having done some more experimentation and 
measurement today I think the main problems were the old dist amp that 
seemed to be injecting all manner of DVB unfriendly crap into the signal 
(now retired!), and many yards of co-ax no longer in the first flush of 
youth. Alas when they built the loft conversion here, it seems they 
built it round the wiring, which is making working out how to re-cable 
an interesting challenge.

> Simple just run a signal cable from a multi output LNB?..

What would that do for me?

-- 
Cheers,

John.

/=================================================================\
|          Internode Ltd -  http://www.internode.co.uk            |
|-----------------------------------------------------------------|
|        John Rumm - john(at)internode(dot)co(dot)uk              |
\=================================================================/

John Rumm wrote:

> Looking at the feed to the distribution amp (with the gain on the 
> masthead set to minimum) we now get:
> 
> Channel Signal  Mux
>          (dBuV)
> 54      48      D5
> 56      48      D2
> 
> 51      74      BBC1

So an A-D level difference of 26 dB.  The 'operating window' here is 
quite small - starting from those levels you'd need the overall 
downstream gain (D/A gain less cable losses etc.) to be between -3 and 
+6 dB to keep to recommended signal levels at the outlets.

> Which are at least 20 dB stronger than the digital muxes. (if you ramp 
> up the gain on the masthead I can push these to over 99 dBuV - which is 
> where my meter gives up!)

The proMHD11V is OK up to over 100 dBuV o/p though, so turning the gain 
up and using a passive network may be quite attractive.  Hang on though, 
  something doesn't quite add up: the gain range of the preamp is around 
15 dB (7 min. to 22 max.) - so as you're getting 74 at min. I'd expect 
about 89 at max., not 99+.

> I have come to the conclusion that the labgear is crap anyway.

What model and vintage of Labgear amp is this?  The only significant 
problem with the CM729x or MSA series 'white amps' was that they took to 
using stupidly cheap electrolytics for the PSU reservoir capacitors, 
with the inevitable result that the caps dry out and lead to a mains hum 
modulation problem, clearly visible as a hum bar on analogue.  That's 
simple to repair of course (470 uF / 25 V, IIRC).  If the gain is low 
and noise figure high it's usually because the input's been zapped by 
lightning, in which case throw it away (oops, sorry, I meant recycle it 
at your nearest WEEE DCF).

>  and the house co-ax wiring leaves much to  be desired.

Therein lies your problem, I agree.

-- 
Andy

Glenn Millar wrote:

> Running a variable gain amplifier at lowest gain will only increase the 
> noise level.

That's rather a sweeping statement that needs a little scrutiny.  Of 
course _any_ amplifier can only reduce the S/N ratio of the signals 
passing through it; what matters is its overall effect in a system. 
"Increase the noise level relative to what" is the point.

Many variables now come into play: the gain and noise figure (NF) of the 
preamp, the following feeder (downlead) loss and the details of the 
following distribution system and receivers.  To consider the effect of 
adding a preamp, or to compare preamp A with preamp B, we can lump the 
downlead, distribution system and receiver together and characterise it 
as a single 'back-end' NF.  Lets assume the following back end:

- downlead loss: 3 dB
- D/A gain:      6 dB
- D/A NF:        4 dB
- cable loss     3 dB (D/A to receiver)
- RX or STB NF   6 dB.

The overall cascaded NF of that lot works out at 9.3 dB and with no 
preamp that is the overall system NF.  The ultimate S/N available from 
any particular aerial is being degraded by 9.3 dB by the time it reaches 
the demodulator in the RX.  (This assumes an antenna noise temperature 
of 290 K, the normal assumption for UHF TV.)

Now if we insert John's proMHD11V set at minimum gain.  This preamp has 
a gain of 7 dB and, by coincidence, also has a NF of about 7 dB.  The 
overall system NF with the preamp inserted becomes 8.1 dB and we've 
achieved a S/N improvement of about 1.2 dB - not much, but the increase 
in the DTT levels will help counter impulsive interference problems. 
Also the implied assertion that running the variable gain preamp at its 
minimum setting could worsen matters is shown to be wrong in this case.

> A fixed low gain amplifier would be better suited.

That's certainly true.  If we used a proMHD11L (gain 9 dB, typ. NF 1.8 
dB) in the same system the overall NF becomes 3.9 dB - 5.4 dB better 
than the no-preamp case.

-- 
Andy

John Rumm wrote:

> The spec on that amp show a max noise of 2.6dB and a minimum gain of 
> supposedly 7dB,

Yes, but not both at the same time.  The quoted NF applies at max. gain. 
  Inevitably the NF rises as the gain is backed-off.  At 10 dB gain 
reduction it's about 4 dB (that's on the full data sheet) and at min. 
gain it's roughly 7 dB (this is not published).

> [...]
> (I note the gain is a bit lower than spec at both ends 

It's a competitively priced TV preamp, not a precision attenuator :~) 
The gain flatness certainly varies as you wind the gain down and does 
tend to be least flat at the minimum setting.

> but that could be down to the fact I was powering the amp from my
> test meter and the batteries were getting low)

The variable gain preamps are quite thirsty (50 mA) and are quite 
sensitive to supply voltage.  The gain will start to drop off quite 
steeply below 11 V or so.

-- 
Andy

In article <08OdnYfaqaXiKfvVnZ2dneKdnZydnZ2d@posted.plusnet>, John Rumm
 scribeth thus
>tony sayer wrote:
>
>>> I have a significant investment in freeview kit, including a topfield 
>>> PVR and network connection for it.
>>>
>>> What I don't have is a bunch of sat boxes, a multiswitch, a quad output 
>>> LNB or any of the wiring infrastructure to make freesat a cost effective 
>>> multiroom setup.
>>>
>> 
>> Didn't you say you can't get freeview anyway earlier?..
>
>You may recall:
>
>http://groups.google.com/group/uk.tech.digital-tv/browse_frm/thread/af31376eece9
>3d26/5c59b06724640147?hl=en&lnk=st&q=group%3Auk.tech.digital-
>tv+rumm#5c59b06724640147
>
>Which was the state of play when we moved in - passable analogue from 
>one Tx and poor from another, and only one mux limping through part time 
>from the better Tx.

And all available from the heavens;)..
>
>I did a lash-up with the original aerial and lots of amplification in 
>all the wrong places to see if with enough signal level I could get 
>anything useful, and did achieve at least most muxes on one TV.

A lot of effort for not a lot..

>
>So now with a new more appropriate aerial I am close to having a fully 
>working multi output setup. Having done some more experimentation and 
>measurement today I think the main problems were the old dist amp that 
>seemed to be injecting all manner of DVB unfriendly crap into the signal 
>(now retired!), and many yards of co-ax no longer in the first flush of 
>youth. Alas when they built the loft conversion here, it seems they 
>built it round the wiring, which is making working out how to re-cable 
>an interesting challenge.
>
>> Simple just run a signal cable from a multi output LNB?..
>
>What would that do for me?

Give you a lot of TV and radio signals?..

No filters or band pass levellers required either
>

-- 
Tony Sayer

tony sayer wrote:
> In article <08OdnYfaqaXiKfvVnZ2dneKdnZydnZ2d@posted.plusnet>, John Rumm

>>> Simple just run a signal cable from a multi output LNB?..
>> What would that do for me?
> 
> Give you a lot of TV and radio signals?..
> 
> No filters or band pass levellers required either
> 

True, but what's the cheapest D-Sat box, that gives you an EPG comparable with 
Freeview's, 50 Quid ?

Cheapest DTT box about 16 quid, if the telly, or DVD recorder is not already 
fitted with a DTT receiver.

Where's the break even point between a complex DTT reception and distribution 
system, and the number and cost of D-Sat receivers required to be fed in the 
house ?

Also the TV channel choice is better on FTA DTT, than FTA/FTV D-Sat (Radio 
choice is the other way round though).

-- 
Mark
Please replace invalid and invalid with gmx and net to reply.

"Mark Carver" <mark.carver@invalid.invalid> wrote in message 
news:6cpi05F3gpprhU1@mid.individual.net...
> Where's the break even point between a complex DTT reception and 
> distribution system, and the number and cost of D-Sat receivers required 
> to be fed in the house ?

When starting from scratch the extra cost of adding satellite IF to all 
outlets on a system of 12 or more points is minimal (per point). However, 
you really need to add a second feed to every location, and that does bump 
up the cost a fair bit.

Bill

In , Mark Carver
<mark.carver@invalid.invalid> wrote:

>Also the TV channel choice is better on FTA DTT, than FTA/FTV D-Sat 

True, but this is only a temporary situation (ie with SD). HD on FTA DTT
is looking to be awful, with 3 channels shoehorned in at low bitrates
being the best we'll get if Ofcom's crazy plan goes ahead. But HD on FTA
DSAT, with far more bandwidth available, should piss all over that.

Mike Henry wrote:
> In , Mark Carver
> <mark.carver@invalid.invalid> wrote:
> 
>> Also the TV channel choice is better on FTA DTT, than FTA/FTV D-Sat 
> 
> True, but this is only a temporary situation (ie with SD). HD on FTA DTT
> is looking to be awful, with 3 channels shoehorned in at low bitrates
> being the best we'll get if Ofcom's crazy plan goes ahead. But HD on FTA
> DSAT, with far more bandwidth available, should piss all over that.

I agree. After almost 10 years of both digital platforms in our house, things 
are now moving towards D-Sat HD and SD being the primary viewing format in the 
living room, with DTT being used in the bedrooms.

The buggers are the continued lack of a Freesat PVR, and ITV-1 SD on D-Sat 
being at a horizontal res of only 544 (ITV-1 on DTT is 704).


-- 
Mark
Please replace invalid and invalid with gmx and net to reply.

In article , Mark Carver
<mark.carver@invalid.invalid> scribeth thus
>tony sayer wrote:
>> In article <08OdnYfaqaXiKfvVnZ2dneKdnZydnZ2d@posted.plusnet>, John Rumm
>
>>>> Simple just run a signal cable from a multi output LNB?..
>>> What would that do for me?
>> 
>> Give you a lot of TV and radio signals?..
>> 
>> No filters or band pass levellers required either
>> 
>
>True, but what's the cheapest D-Sat box, that gives you an EPG comparable with 
>Freeview's, 50 Quid ?

Prices are or will start coming down and theres always second-hand Sky
boxes..

>
>Cheapest DTT box about 16 quid, if the telly, or DVD recorder is not already 
>fitted with a DTT receiver.

16 quid can't be all that good then;(..

>
>Where's the break even point between a complex DTT reception and distribution 
>system, and the number and cost of D-Sat receivers required to be fed in the 
>house ?
>
>Also the TV channel choice is better on FTA DTT, than FTA/FTV D-Sat (Radio 
>choice is the other way round though).
>

But considering the move to HD and the much greater bandwidth available
on D Sat don't you think this is the way to go?..
-- 
Tony Sayer

In article , Mark Carver
<mark.carver@invalid.invalid> scribeth thus
>Mike Henry wrote:
>> In , Mark Carver
>> <mark.carver@invalid.invalid> wrote:
>> 
>>> Also the TV channel choice is better on FTA DTT, than FTA/FTV D-Sat 
>> 
>> True, but this is only a temporary situation (ie with SD). HD on FTA DTT
>> is looking to be awful, with 3 channels shoehorned in at low bitrates
>> being the best we'll get if Ofcom's crazy plan goes ahead. But HD on FTA
>> DSAT, with far more bandwidth available, should piss all over that.
>
>I agree. After almost 10 years of both digital platforms in our house, things 
>are now moving towards D-Sat HD and SD being the primary viewing format in the 
>living room, with DTT being used in the bedrooms.
>
>The buggers are the continued lack of a Freesat PVR, and ITV-1 SD on D-Sat 
>being at a horizontal res of only 544 (ITV-1 on DTT is 704).
>
>
I'm sure when they get their act together on this it will all be
better..
-- 
Tony Sayer

tony sayer wrote:

> But considering the move to HD and the much greater bandwidth available
> on D Sat don't you think this is the way to go?..

I do, but as I implied in the other post, D-Sat for the main telly, DTT for 
the bedrooms and kitchen.

-- 
Mark
Please replace invalid and invalid with gmx and net to reply.

As part of a larger ongoing project that will see a fair bit of 
additional wiring in the house, I created a new entrance into one of the 
areas of roof that had been voided off (this also opens up masses of 
extra storage space).

This provided access all along one side of the roof and a chance to get 
close to much of the coax. All I needed was someone skinny enough to fit 
through the small triangular bit of roof space under each of the dormer 
windows. Fortunately today my mate Martin came to visit and was coerced 
into void exploration mode!

So a nice new CT100 co-ax feed from the aerial itself is now in place 
along with replacement runs to some of the less well performing sockets.

Andy Wade wrote:

> John Rumm wrote:
> 
>> Looking at the feed to the distribution amp (with the gain on the 
>> masthead set to minimum) we now get:
>>
>> Channel Signal  Mux
>>          (dBuV)
>> 54      48      D5
>> 56      48      D2
>>
>> 51      74      BBC1
> 
> So an A-D level difference of 26 dB.  The 'operating window' here is 
> quite small - starting from those levels you'd need the overall 
> downstream gain (D/A gain less cable losses etc.) to be between -3 and 
> +6 dB to keep to recommended signal levels at the outlets.
> 
>> Which are at least 20 dB stronger than the digital muxes. (if you ramp 
>> up the gain on the masthead I can push these to over 99 dBuV - which 
>> is where my meter gives up!)
> 
> The proMHD11V is OK up to over 100 dBuV o/p though, so turning the gain 
> up and using a passive network may be quite attractive.  Hang on though, 

Yup, this is the way I have gone for the moment. I am driving four 
outlets via a passive splitter, and have the masthead amp on close to 
max gain. The digiboxes (Netgems) are reporting approx 40% signal 
strength (Toppy says 99% on most muxes), but channel quality is at least 
85% or better. SNR is typically between 22 and 26 dB on all channels, 
with BER below the limit of the box to measure in most cases. (the 
occational burst up to 1 in 1x10^6 - but within the FECs capability to 
handle it). Video and audio seem "perfect" (well as good as you can get 
for over compressed MPEG2 stuff!)

That will probably do until such a time as I need to bring more of the 
sockets back into commission. At which point I was thinking something 
like the Proception AP01828 or AP01824 would probably do the job nicely.

Would the single AP01838 PSU cope with the amp ad the AP01824?

>  something doesn't quite add up: the gain range of the preamp is around 
> 15 dB (7 min. to 22 max.) - so as you're getting 74 at min. I'd expect 
> about 89 at max., not 99+.

That's 75 measured at the output of the aerial itself, not the masthead 
amp. (74 was what I was seeing at the end of the soggy co-ax from the 
aerial with the amp on minimum gain)

Note also that these measurements have been taken over a few days and we 
are nearly 30 miles from the Tx  - so there is a bit of variation in 
them  anyway. Finally note that beyond 90 dBuV is over spec for accurate 
measurement range on the meter.

>> I have come to the conclusion that the labgear is crap anyway.
> 
> What model and vintage of Labgear amp is this?  The only significant 

CM7296 - not sure of the age.

> problem with the CM729x or MSA series 'white amps' was that they took to 
> using stupidly cheap electrolytics for the PSU reservoir capacitors, 
> with the inevitable result that the caps dry out and lead to a mains hum 
> modulation problem, clearly visible as a hum bar on analogue.  That's 

The visible trait on analogue was a vertical bar roughly in the middle 
of the screen about 20% of the frame width, which showed more noise. 
There was also a horizontal portion about 10% height starting 4/6ths 
down the screen. This gave an inverted "T" effect.

I might have it apart in a bit, and investigate.

> simple to repair of course (470 uF / 25 V, IIRC).  If the gain is low 
> and noise figure high it's usually because the input's been zapped by 
> lightning, in which case throw it away (oops, sorry, I meant recycle it 
> at your nearest WEEE DCF).

That would be the grey one one wheels in the garden then ;-)

>>  and the house co-ax wiring leaves much to  be desired.
> 
> Therein lies your problem, I agree.

Yes - it was quite noticeable how the original coax from masthead to 
splitter managed to lose somewhere between 5 - 7 dB across the board and 
gently roll off a bit more with increasing frequency. As soon as the new 
cable was in there I could not really detect any loss. (as you would 
expect for such a short length). I get the feeling there were some 
interesting notches in its response as well, since even when decoding 
all muxes, there were a small handful of channels that were suffering 
high error rates even when others on the same mux were apparently fine.

(looks like the aerial rigger was not the only one being lazy - the sky 
installer had found another bit of old co-ax to reuse as well - at least 
he joined the cable with a couple of belling lee's and a barrel 
connector, and tucked it under some lead flashing! Since the sky box 
seems happy enough with that, I decided to leave that for another day, 
and just took the precaution of wrapping the join in self amalgamating 
tape and tucking it back under its lead umbrella)


-- 
Cheers,

John.

/=================================================================\
|          Internode Ltd -  http://www.internode.co.uk            |
|-----------------------------------------------------------------|
|        John Rumm - john(at)internode(dot)co(dot)uk              |
\=================================================================/

tony sayer wrote:

> But considering the move to HD and the much greater bandwidth available
> on D Sat don't you think this is the way to go?..

The advent of free HD on DSAT does make it more attractive. I will 
probably upgrade the "main" TV to HD at some point and might swap in a 
HD sat box at that point.

However its probably not attractive enough to want to roll it out as a 
multiroom setup in my case (don't actually watch that much broadcast TV 
anyway), so DTT on all TVs and DSAT on one seems like a reasonable 
compromise without too much extra kit required.

-- 
Cheers,

John.

/=================================================================\
|          Internode Ltd -  http://www.internode.co.uk            |
|-----------------------------------------------------------------|
|        John Rumm - john(at)internode(dot)co(dot)uk              |
\=================================================================/

tony sayer wrote:

> And all available from the heavens;)..
>> I did a lash-up with the original aerial and lots of amplification in 
>> all the wrong places to see if with enough signal level I could get 
>> anything useful, and did achieve at least most muxes on one TV.
> 
> A lot of effort for not a lot..

about 20 mins plugging in extra amps and re jigging cables etc?

Twas enough to prove I did not need a big pile of DSAT boxes, new LNB, 
multiswitch, new outlet plates, and a whole load of extra cable runs - 
some of which would be a PITA to get in.

>> So now with a new more appropriate aerial I am close to having a fully 
>> working multi output setup. Having done some more experimentation and 
>> measurement today I think the main problems were the old dist amp that 
>> seemed to be injecting all manner of DVB unfriendly crap into the signal 
>> (now retired!), and many yards of co-ax no longer in the first flush of 
>> youth. Alas when they built the loft conversion here, it seems they 
>> built it round the wiring, which is making working out how to re-cable 
>> an interesting challenge.
>>
>>> Simple just run a signal cable from a multi output LNB?..
>> What would that do for me?
> 
> Give you a lot of TV and radio signals?..

Well, I have that in one room anyway... that does not make it a trivial 
matter to roll it out round the house.

> No filters or band pass levellers required either

Looks like I managed to get away without that in the end anyway ;-)


-- 
Cheers,

John.

/=================================================================\
|          Internode Ltd -  http://www.internode.co.uk            |
|-----------------------------------------------------------------|
|        John Rumm - john(at)internode(dot)co(dot)uk              |
\=================================================================/

>Note also that these measurements have been taken over a few days and we 
>are nearly 30 miles from the Tx  - so there is a bit of variation in 
>them  anyway. 

Is this from the Sudbury transmitter and if so which direction are you
"seeing" it from?..

>Finally note that beyond 90 dBuV is over spec for accurate 
>measurement range on the meter.
-- 
Tony Sayer

>>For this many outlets?
>>It's a good answer for some applications, but where you wish to watch and
>>record different programmes at multiple outlets it's far from ideal.
>>
>>I run 6 TV's and at 3 of these we also record.
>
> Blimey! your addicted to the telly?..
>
> I should see someone about that!..
>
> U need therapy M8;)..


I don't, I hardly watch it! Ironically this weekend has seen me watch more 
than usual with Glastonbury and Wimbledon!

The main three TV's are kitchen, lounge and kids lounge. Of all our TV's 
(and we actually have 8 altogether) only 2 were bought by us. The others 
have come from (now) dead relatives or salvaged as I couldn't bear to see 
perfectly good TV's skipped! SWMBO watches significantly more than I do, and 
the kids watch about an hour a day.

I struggle to find anything I want to watch.

tony sayer wrote:
>> Note also that these measurements have been taken over a few days and we 
>> are nearly 30 miles from the Tx  - so there is a bit of variation in 
>> them  anyway. 
> 
> Is this from the Sudbury transmitter and if so which direction are you
> "seeing" it from?..

Yup, Sudbury, the Tx is about 7 degrees past due North from us.

-- 
Cheers,

John.

/=================================================================\
|          Internode Ltd -  http://www.internode.co.uk            |
|-----------------------------------------------------------------|
|        John Rumm - john(at)internode(dot)co(dot)uk              |
\=================================================================/

In article <maednZQpc4UJRvXVnZ2dnUVZ8uydnZ2d@posted.plusnet>, Doctor D
 scribeth thus
>
>
>>>For this many outlets?
>>>It's a good answer for some applications, but where you wish to watch and
>>>record different programmes at multiple outlets it's far from ideal.
>>>
>>>I run 6 TV's and at 3 of these we also record.
>>
>> Blimey! your addicted to the telly?..
>>
>> I should see someone about that!..
>>
>> U need therapy M8;)..
>
>
>I don't, I hardly watch it! Ironically this weekend has seen me watch more 
>than usual with Glastonbury and Wimbledon!
>
>The main three TV's are kitchen, lounge and kids lounge. Of all our TV's 
>(and we actually have 8 altogether) only 2 were bought by us. The others 
>have come from (now) dead relatives or salvaged as I couldn't bear to see 
>perfectly good TV's skipped! 

My dad was like that .. collected redundant tea pots;!..

>SWMBO watches significantly more than I do, and 
>the kids watch about an hour a day.
>
>I struggle to find anything I want to watch. 
>

Me too;)...
-- 
Tony Sayer

In article <ic6dncIgPatXZPXVnZ2dnUVZ8uGdnZ2d@posted.plusnet>, John Rumm
 scribeth thus
>tony sayer wrote:
>>> Note also that these measurements have been taken over a few days and we 
>>> are nearly 30 miles from the Tx  - so there is a bit of variation in 
>>> them  anyway. 
>> 
>> Is this from the Sudbury transmitter and if so which direction are you
>> "seeing" it from?..
>
>Yup, Sudbury, the Tx is about 7 degrees past due North from us.
>

Good job then your aerials aren't pointing to the continent. A mate of
mine who is North West of Sudbury has had to go satellite 'cos of the co
channel interference in warm weather etc..
-- 
Tony Sayer

tony sayer wrote:

>>> Is this from the Sudbury transmitter and if so which direction are you
>>> "seeing" it from?..
>> Yup, Sudbury, the Tx is about 7 degrees past due North from us.
>>
> 
> Good job then your aerials aren't pointing to the continent. A mate of
> mine who is North West of Sudbury has had to go satellite 'cos of the co
> channel interference in warm weather etc..

IIRC Sudbury also has a "shaped" radiation pattern to try and minimise 
impact on our continental neighbours.



-- 
Cheers,

John.

/=================================================================\
|          Internode Ltd -  http://www.internode.co.uk            |
|-----------------------------------------------------------------|
|        John Rumm - john(at)internode(dot)co(dot)uk              |
\=================================================================/

John Rumm wrote:

> Yup, this is the way I have gone for the moment. I am driving four 
> outlets via a passive splitter, and have the masthead amp on close to 
> max gain. The digiboxes (Netgems) are reporting approx 40% signal 
> strength (Toppy says 99% on most muxes), but channel quality is at least 
> 85% or better.

Those percentages on boxes are pretty meaningless, IME.  Use Terry.

> SNR is typically between 22 and 26 dB on all channels, 
> with BER below the limit of the box to measure in most cases. (the 
> occational burst up to 1 in 1x10^6 - but within the FECs capability to 
> handle it). Video and audio seem "perfect" (well as good as you can get 
> for over compressed MPEG2 stuff!)

Yes - the modem may be perfect, end-to-end BER of 1E-11, but GIGO 
applies as ever :~).

> That will probably do until such a time as I need to bring more of the 
> sockets back into commission. At which point I was thinking something 
> like the Proception AP01828 or AP01824 would probably do the job nicely.

The AP numbers are CPC's own stock codes.  Easier for me if you quote 
the Proception product codes, all of which start with "pro".

> Would the single AP01838 PSU cope with the amp ad the AP01824?

You mean the masthead amp (proMHD11V) and the proAMP108U 8-way?  The 
total current there (~75 mA) is within the PSU's 100 mA rating, but the 
'108U amp won't pass power through to the preamp.  Unless you want to 
make up your own line power splitting arrangements (not trivial) you'll 
need separate PSU's.  The proAMP108U can be powered locally from a 
proPSA123 adaptor (AP01841), or if any of your DTT boxes will provide 5 
V on the aerial socket that will also do the job.

>> What model and vintage of Labgear amp is this?  The only significant 
> 
> CM7296 - not sure of the age.

Definitely not crap, unless it's broken in some way.

> The visible trait on analogue was a vertical bar roughly in the middle 
> of the screen about 20% of the frame width, which showed more noise. 
> There was also a horizontal portion about 10% height starting 4/6ths 
> down the screen. This gave an inverted "T" effect.

That's cross-modulation from another channel, the bars being the line 
(vertical) and field (horiz) blanking intervals and sync pulses.  The 
whole pattern will usually drift slowly across the screen unless the 
syncs are locked at source.  Turning the input level down should stop 
that.  If the pictures then look noisy it's down to the excessive losses 
in the distribution cables again.

> Yes - it was quite noticeable how the original coax from masthead to
> splitter managed to lose somewhere between 5 - 7 dB[...] I get the
> feeling there were some interesting notches in its response as well,

It only takes one or two dubious braid connections in Belling-Lee type 
plugs or saddle & clamp connections to screw-up the frequency response 
with all manner of suck-outs and dips, so yes, that's very probable.

-- 
Andy

Andy Wade wrote:

>> Yup, this is the way I have gone for the moment. I am driving four 
>> outlets via a passive splitter, and have the masthead amp on close to 
>> max gain. The digiboxes (Netgems) are reporting approx 40% signal 
>> strength (Toppy says 99% on most muxes), but channel quality is at 
>> least 85% or better.
> 
> Those percentages on boxes are pretty meaningless, IME.  Use Terry.

Indeed - althought they are handy in the sense that if the box says 
channel quality is fair or poor you can usually be assured of visible 
drop outs or worse IME.

>> That will probably do until such a time as I need to bring more of the 
>> sockets back into commission. At which point I was thinking something 
>> like the Proception AP01828 or AP01824 would probably do the job nicely.
> 
> The AP numbers are CPC's own stock codes.  Easier for me if you quote 
> the Proception product codes, all of which start with "pro".

Oops sorry, make that PROAMP28R and PROAMP108U

>> Would the single AP01838 PSU cope with the amp ad the AP01824?
> 
> You mean the masthead amp (proMHD11V) and the proAMP108U 8-way?  The 

yup...

> total current there (~75 mA) is within the PSU's 100 mA rating, but the 
> '108U amp won't pass power through to the preamp.  Unless you want to 
> make up your own line power splitting arrangements (not trivial) you'll 

ah, good point, did not think of that! ;-)

Presumably the PROAMP28R with its own PSU would be preferable then?

> need separate PSU's.  The proAMP108U can be powered locally from a 
> proPSA123 adaptor (AP01841), or if any of your DTT boxes will provide 5 
> V on the aerial socket that will also do the job.

Toppy has the option, not sure about the others.

>>> What model and vintage of Labgear amp is this?  The only significant 
>>
>> CM7296 - not sure of the age.
> 
> Definitely not crap, unless it's broken in some way.
> 
>> The visible trait on analogue was a vertical bar roughly in the middle 
>> of the screen about 20% of the frame width, which showed more noise. 
>> There was also a horizontal portion about 10% height starting 4/6ths 
>> down the screen. This gave an inverted "T" effect.
> 
> That's cross-modulation from another channel, the bars being the line 
> (vertical) and field (horiz) blanking intervals and sync pulses.  The 
> whole pattern will usually drift slowly across the screen unless the 
> syncs are locked at source.  Turning the input level down should stop 
> that.  If the pictures then look noisy it's down to the excessive losses 
> in the distribution cables again.

The noise patten was locked in place with no run-through, and was 
present even with a direct feed from the original aerials - a totally 
passive setup with no individual channel above about 64 dBuV.

Oddly the pattern looked like cross modulation in terms of position, but 
  without any of the visible changes in any other part of the screen as 
you would normally see with interference from another "live" channel - 
no movement or variation in brightness or silhouette type effects.

Another reason I have my doubts about the amp is that when we arrived 
here it appeared as if the amp had been wired out of the distribution 
system altogether by the previous owners - basically directing the 
aerial feed to one socket only, bypassing the amp. Next time I see them 
I will ask why they did it!

>> Yes - it was quite noticeable how the original coax from masthead to
>> splitter managed to lose somewhere between 5 - 7 dB[...] I get the
>> feeling there were some interesting notches in its response as well,
> 
> It only takes one or two dubious braid connections in Belling-Lee type 
> plugs or saddle & clamp connections to screw-up the frequency response 
> with all manner of suck-outs and dips, so yes, that's very probable.

Why do so many people who connect to a outlet plate with a traditional 
clamp and centre terminal have to leave half an inch of unshielded inner 
poking out the far side of the terminal?

Talking of saddle clamps, I must get some new screened outlet plates to 
replace the manky collection we have here...

In fact I am tempted to just drill some blanking plates and mount a 
female to female F type barrel connector on the plate, and connect the 
coax via a twist on right angled f plug.

-- 
Cheers,

John.

/=================================================================\
|          Internode Ltd -  http://www.internode.co.uk            |
|-----------------------------------------------------------------|
|        John Rumm - john(at)internode(dot)co(dot)uk              |
\=================================================================/

In article <M-mdnSeDr_751PTVnZ2dnUVZ8hydnZ2d@posted.plusnet>, John Rumm
 scribeth thus
>tony sayer wrote:
>
>>>> Is this from the Sudbury transmitter and if so which direction are you
>>>> "seeing" it from?..
>>> Yup, Sudbury, the Tx is about 7 degrees past due North from us.
>>>
>> 
>> Good job then your aerials aren't pointing to the continent. A mate of
>> mine who is North West of Sudbury has had to go satellite 'cos of the co
>> channel interference in warm weather etc..
>
>IIRC Sudbury also has a "shaped" radiation pattern to try and minimise 
>impact on our continental neighbours.
>
>
>
Just like they -shape- theirs to annoy us;(....
-- 
Tony Sayer

John Rumm wrote:

> Presumably the PROAMP28R with its own PSU would be preferable then?

Yes (FAOD that's mains powered with built-in PSU), although you don't 
need the R version unless you plan to feed the UHF i/p from the o/p of a 
Sky box etc.  The plain proAMP28 has some advantages: (i) it will also 
power the preamp, assuming there's nothing in the way that will block 
DC; (ii) it doesn't have 9 V on all the o/p's and (iii) you can use the 
'full' o/p for expanding beyond 8 outlets.

>>> CM7296 - not sure of the age.
>>
>> Definitely not crap, unless it's broken in some way.
>>
[snip]
> The noise patten was locked in place with no run-through, and was 
> present even with a direct feed from the original aerials - a totally 
> passive setup with no individual channel above about 64 dBuV.
> 
> Oddly the pattern looked like cross modulation in terms of position, but 
>  without any of the visible changes in any other part of the screen as 
> you would normally see with interference from another "live" channel - 
> no movement or variation in brightness or silhouette type effects.

Very odd.  I'm not sure what to make of that, except that if it was 
happening at such a low level and the signal going in was free fro the 
effect it does rather point to the amplifier being broken.

> Why do so many people who connect to a outlet plate with a traditional 
> clamp and centre terminal have to leave half an inch of unshielded inner 
> poking out the far side of the terminal?

It's traditional.  They used to do it on saddle & clamp mastheads too, a 
whole inch sometimes on some of the ones we used to get back at Labgear.

> Talking of saddle clamps, I must get some new screened outlet plates to 
> replace the manky collection we have here...
> 
> In fact I am tempted to just drill some blanking plates and mount a 
> female to female F type barrel connector on the plate, and connect the 
> coax via a twist on right angled f plug.

That's one approach.  Another would be our new slim-line single screened 
'IEC' outlet
http://www.blake-uk.com/page/amplifiers_distribution/proslo

-- 
Andy

Andy Wade wrote:

> [snip]
>> The noise patten was locked in place with no run-through, and was 
>> present even with a direct feed from the original aerials - a totally 
>> passive setup with no individual channel above about 64 dBuV.
>>
>> Oddly the pattern looked like cross modulation in terms of position, 
>> but  without any of the visible changes in any other part of the 
>> screen as you would normally see with interference from another "live" 
>> channel - no movement or variation in brightness or silhouette type 
>> effects.
> 
> Very odd.  I'm not sure what to make of that, except that if it was 
> happening at such a low level and the signal going in was free fro the 
> effect it does rather point to the amplifier being broken.

That was the conclusion I came to...

>> Talking of saddle clamps, I must get some new screened outlet plates 
>> to replace the manky collection we have here...
>>
>> In fact I am tempted to just drill some blanking plates and mount a 
>> female to female F type barrel connector on the plate, and connect the 
>> coax via a twist on right angled f plug.
> 
> That's one approach.  Another would be our new slim-line single screened 
> 'IEC' outlet
> http://www.blake-uk.com/page/amplifiers_distribution/proslo

Those look handy... where can one order them from? (your site seems to 
have a basket, but no way of adding to it!)


(I don't actually need "slim" in this house since they seem to have used 
35mm deep boxes everywhere - even on the studwork walls upstairs they 
have placed metal boxes on nogginigs in preference to using dry lining 
boxes).

-- 
Cheers,

John.

/=================================================================\
|          Internode Ltd -  http://www.internode.co.uk            |
|-----------------------------------------------------------------|
|        John Rumm - john(at)internode(dot)co(dot)uk              |
\=================================================================/

On Wed, 02 Jul 2008 05:01:29 +0100, John Rumm 
wrote:

>> http://www.blake-uk.com/page/amplifiers_distribution/proslo
> 
> Those look handy... where can one order them from? (your site seems to 
> have a basket, but no way of adding to it!)

Their site is shite. They really need to get themselves someone who knows
what they are doing with such things.

"John Rumm"  wrote in message 
news:_fqdnYjw-6ICYPfVnZ2dnUVZ8uudnZ2d@posted.plusnet...
> (I don't actually need "slim" in this house since they seem to have used 
> 35mm deep boxes everywhere - even on the studwork walls upstairs they have 
> placed metal boxes on nogginigs in preference to using dry lining boxes).

There you go Andy. You put your heart and soul into researching what the 
public wants and designing the perfect product, then some awkward bastard 
wants something different. You just can't win . . .

Bill

Bill Wright wrote:
> "John Rumm"  wrote in message 
> news:_fqdnYjw-6ICYPfVnZ2dnUVZ8uudnZ2d@posted.plusnet...
>> (I don't actually need "slim" in this house since they seem to have used 
>> 35mm deep boxes everywhere - even on the studwork walls upstairs they have 
>> placed metal boxes on nogginigs in preference to using dry lining boxes).
> 
> There you go Andy. You put your heart and soul into researching what the 
> public wants and designing the perfect product, then some awkward bastard 
> wants something different. You just can't win . . .

Well if its a consolation, I have made a mental note that should I need 
slim screened sockets I know where to get them (well I know who makes 
them - even if I don't know where to get them!) ;-)



-- 
Cheers,

John.

/=================================================================\
|          Internode Ltd -  http://www.internode.co.uk            |
|-----------------------------------------------------------------|
|        John Rumm - john(at)internode(dot)co(dot)uk              |
\=================================================================/

John Rumm wrote:

> Well if its a consolation, I have made a mental note that should I need 
> slim screened sockets I know where to get them (well I know who makes 
> them - even if I don't know where to get them!) ;-)

They're pretty good whatever the box depth, actually.  More wiring space 
is always welcome, especially with the single-gang accessories.

Anyway John, if you go back to the same web page you'll now find a 'buy' 
button at top right.  This will take you to basket entry.  For some 
reason it got left off this page, the webmaster tells me.

I'm well aware that the Blake web site leaves a lot to be desired.  It's 
an in-house effort that's grown a bit out of control and needs radical 
simplification.  Give it time, and we'll have something better.

-- 
Andy

Andy Wade wrote:

>> Well if its a consolation, I have made a mental note that should I 
>> need slim screened sockets I know where to get them (well I know who 
>> makes them - even if I don't know where to get them!) ;-)
> 
> They're pretty good whatever the box depth, actually.  More wiring space 
> is always welcome, especially with the single-gang accessories.

True, especially with foiled coax like CT100.

> Anyway John, if you go back to the same web page you'll now find a 'buy' 
> button at top right.  This will take you to basket entry.  For some 
> reason it got left off this page, the webmaster tells me.

Ah, that works better ;-) Thanks Andy.

> I'm well aware that the Blake web site leaves a lot to be desired.  It's 
> an in-house effort that's grown a bit out of control and needs radical 
> simplification.  Give it time, and we'll have something better.

Maybe, but I will take functional over flashy every time!


-- 
Cheers,

John.

/=================================================================\
|          Internode Ltd -  http://www.internode.co.uk            |
|-----------------------------------------------------------------|
|        John Rumm - john(at)internode(dot)co(dot)uk              |
\=================================================================/